Problems from 2021 ICPC North America Regional Programming Contests (March 5 2022)

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Archery Accuracy0.018711193429%6.9Harden
Average Character0.00133334138842%1.7Easyen
Black and White0.1359228613347%5.0Mediumen
Circle Bounce0.002001759655%4.3Mediumen
Diagonals0.0018841555737%7.4Harden
Dorm Room Divide0.03580123315012%6.9Harden
Double Password0.00193492196956%1.7Easyen
Fail Them All!0.008994069624%8.3Harden
Hopscotch 5000.1187845310623%7.7Harden
Overdraft0.0038190989447%2.0Easyen
Problem Set Construction0.01940493367%4.8Mediumen
Reversibly Cyclic Strings0.001346821646%3.4Mediumen
Rise and Fall0.008880421226%4.4Mediumen
Scaling Recipe0.0013151372348%1.8Easyen
Shortest Missing Subsequences0.098862619034%5.9Harden
Square Bounce0.005031064542%4.5Mediumen
Tetris Generation0.0090106127025%5.6Harden
Tournament Seeding0.0333039818246%4.0Mediumen
Tree Hopping0.0289369017726%6.5Harden
Who Goes There?0.0011992731134%4.2Mediumen
XOR Island0.002912008140%6.1Harden